1. Field of the Invention
This invention relates to a successive screw feeder driver operated such that when a screw for use in fixing a plate material such as a wooden plate or a metallic plate or the like against a wall surface or a floor surface or the like in a successive manner, a screw chain having some screws connected continuously is lifted up to prevent this screw chain from being wound around a seat surface of a screw head section.
2. Description of the Related Art
In the prior art, it has been proposed to provide a successive screw feeder driver 51 capable of driving the screws in a successive manner to fix a plate member such as a wooden plate or a metallic plate or the like against a wall surface or a floor surface and the like. As shown in FIGS. 11 and 12, this type of successive screw feeder driver 51 is constructed such that a rod-like bit 54 for use in driving a screw which corresponds to a screw driver of a normal type tool is arranged at the front section of a screw driving mechanism body 53 having a drive unit 52 stored therein and the bit 54 is rotated by the drive unit 52 to drive each of the screws S.
In the case that the screw S is driven by the prior art successive screw feeder driver 51, a worker loads a screw chain 11 having many screws S, S . . . successively arranged side by side on a fine rope in the main body 55 of the screw feed mechanism body 55 located at the extremity end of the successive screw feeder driver 51 as shown in FIG. 12 and then arranges the leading end screw S of the screw chain 11 at a drive action applying position set by the bit 54. The worker inserts the extremity end 11a of the screw chain 11 projected toward a side part of the screw S into a guide passage and further the worker gradually drives the screw S against the wall surface or the like with the bit 54 rotated at this position by the drive unit 52. The screw feed mechanism body 55 gradually moves back toward the screw driving mechanism body 53 in concurrent with the driving of the screw S. The screw feed mechanism body 55 abuts against the screw driving mechanism body 53 and stops. At this time, a clutch of the machine is released to complete a driving work for one piece of the screw S.
However, as shown in FIGS. 13(a) and (b), the aforesaid prior art successive screw feeder driver 51 had a problem that the screw chain 11 with the screw S being removed away from it is held between the seat surface C of the screw S and the wall surface or the like. In addition, in the case that the screw chain 11 having such a screw S as above removed from it is held between the screw S and the wall surface or the like, a next screw S placed to the former one in the screw chain 11 is sometimes transferred while it is being kept in its inclined state. Accordingly, there was a problem in the prior art successive screw feeder driver 51 that the screw S can not be driven under its appropriate state. Further, the extremity end of the rotating bit 54 was displaced from the engaging position of the head section of the screw S and the screw S could not be rotated.
In view of the foregoing, as shown in FIGS. 14(a), (b), the screw S applied in the successive screw feeder driver 51 was made in the prior art such that a part between the head section of the screw S and the threaded part of it was formed into an inverse-conical shape, a so-called pan shape. This screw S has some structural features that a ring-like portion holding the screw chain 11 may easily be cut and then the screw chain 11 can be easily released from the head section of the screw S.
In the case that the screw S is transferred to the driving action applying position, a feeder claw 57 constituting the screw feeder mechanism is operated as shown in FIGS. 15(a), (b), (c) and (d). At first, the feeder claw 57 is engaged with the threaded part of the screw S (FIG. 15(a)). Then, the screw S is transferred up to the driving action applying position at the upper surface of the screw feed mechanism body 55 (FIG. 15(b)). The extremity end 57a of the feeder claw 57 passes below the threaded part of the subsequent screw S while it is being rotated against a spring force and inclined in concurrent with the driving operation of the screw S (FIG. 15(c)). Lastly, it is recovered and moved upright in such a way that the extremity end part 57a of the feeder claw 57 is projected out at the side surface of the threaded part of the subsequent screw S (FIG. 15(d)). However, the extremity end part 57a of the feeder claw 57 is merely made to be steep. Due to this fact, in the case that the subsequent screw S is released from its predetermined position and the extremity end part 57a of the feeder claw 57 can not pass below the threaded part under a state in which it is being inclined, the feeder claw 57 can not be recovered back and made to be upright in such a way that the extremity end part 57a is projected at the side surface of the threaded part. There occurred a problem that the screw S is transferred in an idling manner due to the fact that this feeder claw 57 can not hold the subsequent screw S, but moves up to the driving action applying position of the bit 54.
The present invention has been invented in view of the aforesaid problems and it is an object of the present invention to provide a successive screw feeder driver in which even if the screw has a flat seat surface, this screw can be driven under an appropriate state against the fixed surface without causing the screw chain to be held between it and the seat surface of the head part by lifting up the extremity end of the screw chain in an upward direction when the screw is driven.